THE JENIKE FLUIDIZATION SEGREGATION
TESTER
US Patent 6,487,921 B1
ASTM Standard D6941-03
Capabilities
The Jenike Fluidization Segregation Tester measures
the tendency of powders or other bulk solids to segregate
by the fluidization segregation mechanism.
- Simulates the top-to-bottom segregation
effects of gas flow through a bulk material, e.g.,
upon filling a bin, rapid blending, or pneumatic
conveying
- Allows comparison of one material
to another
- Provides computer controlled gas
flow rate for repeatable, operator independent
testing
Fluidization can cause vertical segregation, i.e.,
horizontal layers of fines and coarse. Fine particles
generally have a lower permeability than coarse particles
and therefore tend to retain air longer. Thus on
filling a hopper, the coarse particles are driven
into the bed while the fine particles remain fluidized
near the top surface. This can also occur after tumble
blending if the material is fluidized during blending.
Air entrainment often develops in materials that
contain a significant percentage of particles below
100 microns in size. Fluidization segregation is
likely to occur when fine materials are pneumatically
conveyed, filled or discharged at high rates, or
if gas counterflow is present.
General
Testing Procedure
- Pour a measured sample into the assembled tester,
using the top of the expansion chamber as a funnel.
Place the cap and filter on top of the funnel,
and secure.
- Set the air flow rate and duration on the controller.
The fluidization/deaeration cycle proceeds automatically.
- Once deaeration is complete, rotate the handle
to cause the sample contained within each section
to drop into its appropriate collection cup. This
unique design provides fast, easy sample collection.
- Split the samples as needed, using proper techniques,
to obtain the correct quantity required for analysis.
Primary Operational Components and Accessories
- Air flow rate and timing controller
- Screw-on sealing cap
- Paper filter media (1 pkg. of 100)
- Air/Particle separation chamber /
Funnel
- Upper sample chamber section
- Middle sample chamber section
- Lower sample chamber section
- Porous sintered metal air distributor
- Glass sample collection containers
(24)
- Requires 110v power and regulated
air supply
THE
JENIKE SIFTING SEGREGATION TESTER
ASTM
Standard D6940-03
Capabilities
The Jenike Sifting Segregation Tester measures the
tendency of powders or other bulk solids to segregate
by the sifting
segregation mechanism.
- Simulates the side-to-side segregation
effects of a free-flowing material discharging
from a hopper
- Provides a trend through a fill/discharge
cycle
- Allows comparison of one material
to another
- Allows multiple fill/discharge cycles
- Typically provides both mass flow
and funnel flow discharge patterns
Sifting, which is a process by which smaller particles
move through a matrix of larger ones, is the most
common method of segregation. This mechanism is most
likely to occur when handling particles with different
particle size and when there is interparticle motion,
such as during filling, transfer, etc.
General
Testing Procedure
Fill the upper hopper, then discharge the material
to the lower hopper. Steep and shallow angle cones
are provided for use as the upper or lower hoppers.
The preferred method is to use the steep hopper above
the shallow hopper. Discharge the contents of the
lower hopper and collect the samples for analysis.
A variation on this test method is to recirculate
the material until a steady-state is reached. This
tester is specially designed to make this procedure
easy. By recirculating the material, the "signal
strength" of the material's segregation tendency
is intensified, and the initial state of the blend
is less critical.
Primary Operational Components
- Two hoppers with steep cones
- Two hoppers with shallow cones, each
with a slidegate and stainless steel support legs
- Glass sample collection containers
(24)
References
"Bench Scale Segregation Tests as a Predictor of
Blend Sampling Error," by J.K. Prescott, P.J. Ramsey,
et al, presented at the AAPS 2000 annual meeting.
Copies are available upon request.
"A Method to Quantitatively Describe Powder Segregation
During Discharge from Vessels," by A. Alexander,
M. Roddy, D. Brone, J. Michaels, and F. Muzzio, published
in Pharmaceutical Technology, Yearbook 2000, pp.
6-21.
EQUIPMENT AVAILABILITY
The test equipment is available for sale directly
from Jenike & Johanson, Inc. For additional
information or pricing, contact us at (978) 649-3300,
by fax at (978) 649-3399, or by e-mail to test-equip12@jenike.com.
WARRANTY SUMMARY
For a period of one year, we will repair or replace
any defects in materials or workmanship free of charge.
